Dave is right on the money!I would double check the Mav in boiling water just to be sure it is accurate since there is such a big difference between the two. It only takes a few minutes to do a boil test, minutes well worth it to me to know!
No. Adjustable thermometers will have a small nut on the backside of the dial (outside). Hold the nut with a small crescent wrench and hold and turn the dial case till pointer shows correct temp.I would have to take the glass off the thermometer?